Frost dates · South Dakota
South Dakota frost dates, county by county.
Last spring frost and first fall frost probability data for all 66 counties in South Dakota, computed from the NOAA 1991–2020 Climate Normals. Every county page surfaces the full probability table at three temperature thresholds plus crop-specific planting guidance.
Variation across South Dakota
25 days separate the earliest and latest counties.
The median last spring frost in Minnehaha County is April 15 — 25 days earlier than Custer County at May 10. Statewide averages aren't useful planting tools; pick your county below for the data that actually applies to your fields.
By geography
South Dakota counties on the map.
Each polygon is a county. Click for full frost-date detail. Color shows last-spring-frost timing — sage = earliest, amber = latest.
MapList
Last spring frostEarliestMedianLatest
66 counties · click any county for full frost data